Fix formatting issues in README file.

Quoting from the bug report:

The pstack library has been included in MySQL since version
4.0.0. It's useless and should be removed.

Details: According to its own documentation, pstack only works
on Linux on x86 in 32 bit mode and requires LinuxThreads and a
statically linked binary. It doesn't really support any Linux
from 2003 or later and doesn't work on any other OS.

The --enable-pstack option is thus deprecated and has no effect.

Updated the README file.

https://svn.innodb.com/svn/plugin/trunk/build/source_release.sh
which takes it from
https://svn.innodb.com/svn/plugin/trunk/support/README-source

Add a README file containing simple instructions how to build
the plugin from source.

  Added LICENSE.mysql, removed LICENSE.doc README.NW.
  Removed obselete section about MySQLEULA.txt and README.NW.
README:
  Added reference to the EXCEPTIONS-CLIENT file.
  Changed reference to the commercial license file.
  Corrected references into chapters in the manual.
.del-MySQLEULA.txt~4a1afd9284f9be5a:
  Delete: Docs/MySQLEULA.txt

  Typo (bug#17167)

  Update README (2nd try)

  Move to 4.1
README:
  It is just test, ignore. My first attempt to push into bk